This paper is meant to be helpful for those teachers who face difficulties while working with mentally ill students in their classrooms, because the number of mentally ill patients in Japan is increasing. This longitudinal study is a report on two students who suffer from depression and bipolar disorder and uses semistructured interviews, classroom notes, and email exchanges. I gave additional learning support to the students while teaching them English. As a result of instruction and support, these students reentered university, graduated, and started working. Findings suggest that English lessons gave them confidence and paved their ways to recovery. Moreover, with encouragement and additional time, they overcame problems such as lack of concentration and impaired memory.